Cartridges for wound rolls of web material are known which require that the web be wound into a preassembled cartridge. The web must be inserted through an opening in a wall of the cartridge, attached to a spool inside the cartridge and then wound into the cartridge to form a wound roll. Particularly in such cartridges for photographic film, the opening is narrow and at least partially obstructed by a light-shielding door. Because of desired high winding speeds, which require higher tension than would be seen in a camera, and because of the narrowness of this opening, scratching of the film has been a great cause of concern. Also, the attachment end of the film must be reliably presented at a winding station, to facilitate engagement by a tool for attaching the film to the spool. And, some tension must be maintained on the film during its insertion into the cartridge and attachment to the spool, to ensure that the film will not disengage from the attachment tool.